1. Field of Invention
This invention relates to a large capacity general purpose vise that has an adjustable and extendable back jaw while also being able to be operated in a normal horizontal position or be pivoted upward to a vertical operating position.
2. Description of Prior Art
Most vises have a fixed jaw mounted upon a vise body and a movable jaw body resting within or upon the vise body while being movable by a vise screw. Other clamping devises also exist which use a piston-cylinder to directly push a movable jaw or jaws toward a fixed jaw. In either case, the clamping capacities are normally small in relation to the massive area needed to accommodate the function of the vise.
Several types of workholding devises have been presented in earlier patents. U.S. Pat. No. 4,685,661 to Slocum (1987), foreign patent SU 795863 to Shad (1981), foreign patent SU 0831496 to Ivan (1981), and foreign patent EP 0432019 A2 to Kosmek (1991) work with cylinder-pistons that directly move the workholder jaw or jaws. These clamping devises are complicated and expensive to construct. It is unlikely that devises like these could be manufactured to sell in the common market place.
U.S. Pat. No. 5,098,073 issued to Lenz (1992) shows a vise having two jaws which move simultaneously toward a fixed jaw and are operated by a vise screw. U.S. Pat. No. 5,149,071 issued to Oliveira (1992) has a pair of jaws movable toward two fixed jaws and is primarily designed to hold round objects. U.S. Pat. No. 4,413,818 issued to Lenz (1983) shows a vise having a fixed jaw and another jaw movable by a vise screw while the vise body can be clamped to a table while resting on its bottom or either of the two sides. U.S. Pat. No. 4,736,935 issued to Vasapolli shows a vise having a movable jaw body which clamps to the vise body while a first jaw is adjustable and a second jaw can be clamped and also slid on an incline of the movable jaw body. Foreign patent SU 0865598 issued to Bale (1981) shows a vise having a rotating cylinder to directly drive a movable jaw towards a fixed jaw. U.S. Pat. No. 4,968,012 issued to Haddad (1990) shows a workpiece holding apparatus for holding a workpiece in a predetermined position. U.S. Pat. No. 5,110,093 to Merjanian (1992), U.S. Pat. No. 5,156,382 to Saeda (1992), and foreign patent FR 2595062 to Rena (1987) show inventions with a means for changing the workholders mounted position. Although these prior workholding devises may work fine for their intended usages, most have characteristics which limit their uses to specific kinds of tasks and most were designed to be used primarily in machine shops or for industrial uses. These devises also suffer from a number of other disadvantages:
(a) The devises using a vise screw lack the ability to quickly adjust the movable jaw or jaws in relation to clamping workpieces.
(b) The cylinder piston operated devises are bulky and expensive to manufacture.
(c) Their maximum clamping capacities are relatively small in relation to the overall size of the devise.
(d) They lack the ability to pivot to a vertical position to change the clamping direction of their jaws.
Accordingly, this vise has been designed in a uniquely different manner for several reasons. Some of the objects and advantages of my present invention are:
(a) to provide a vise where the clamping capacities between its jaws are quickly and easily changeable;
(b) to provide a vise which has larger than normal maximum workpiece holding capacity in relation to the overall length of its body;
(c) to provide a vise having more than one clamping location;
(d) to provide a vise able to clamp objects at two locations at the same time;
(e) to provide a vise which can be changed from a horizontal to a vertical working position;
(f) to provide a lightweight yet powerful vise having a reasonably low manufacturing cost;
(g) to provide a vise requiring very little manual force to apply a great clamping force;
(h) to provide an affordable vise which has work applications suitable for normal household, building trade and industrial uses.
Thus it is easy to recognise the definite and distinctive features contributing to the differences between this invention and prior inventions having clamping abilities. Further benefits and advantages will become apparent from a consideration of the ensuing description and drawings.